Available Definitions:
1) n. - A corroding or sloughing ulcer; esp. a spreading gangrenous ulcer or collection of ulcers in or about the mouth; -- called also water canker, canker of the mouth, and noma.
2) n. - Anything which corrodes, corrupts, or destroy.
3) n. - A disease incident to trees, causing the bark to rot and fall off.
4) n. - An obstinate and often incurable disease of a horse's foot, characterized by separation of the horny portion and the development of fungoid growths; -- usually resulting from neglected thrush.
5) n. - A kind of wild, worthless rose; the dog-rose.
6) v. t. - To affect as a canker; to eat away; to corrode; to consume.
7) v. t. - To infect or pollute; to corrupt.
8) v. i. - To waste away, grow rusty, or be oxidized, as a mineral.
9) v. i. - To be or become diseased, or as if diseased, with canker; to grow corrupt; to become venomous.